Good that you said you notice 69% diff... coz this game scale horizontally and vertically so is 3200*1800 vs 3840*2160 basically 70% + shadow quality difference
Look at what it means in terms of pixel density, the "relative" scale is probably not the best metric, just like on phones/tablets once people had "retina" resolutions having more pixel density became a non issue, you have reached the useful level of details, 4k or near 4k has given us that level of performance for image reproduction on TVs.
We are going to have the same argument as the last couple of generation, but it's true that it has become less relevant (720p vs 560p was way worse than 1080p vs 900p which is much more noticeable than 1800p vs 2160p).
The reasons are:
- Scaling on 4K TVs/monitors is much better because the base pixels are pretty small, the artefacts are much harder to see--even if you know what to look for
- Pixel density is "high enough" above 1080p on a 4k TV each resolution step is much harder to discern
- Also, with dynamic resolutions this "difference" could last for a fraction of a second at a time
- If you have the choice between few drops to 1800p vs few frame rate drops to the mid 50s (or whatever) does it really matter AT ALL? I mean, it's a nice conversation starter with the girls, but beyond that is pretty much only telling us that these machines are functionally equal to one another.